Centuri BT60 Vulcan Upscale

[JAL3]

I used the same cone. I'm sure that I'll have to turn a balsa cone for the BT70 version. There's just not that many cones made in that size. If you would like one, let me know. I've got the balsa on hand.

As a matter of fact, I probably would. I have not looked to see what's availible for a BT70 yet.

I got some commitments to get some things built before I tackle that one. I've commited to a couple of test programs and Gordon is making some custom parts for a scale project. I also want to see how the 60 does.

Thanks for the offer. I hope the 60 version will be ready for next saturday!

 

[evil ed]

These big ones are fun, aren't they? Can't wait to do an even larger upscale of the Vulcan. I figure, (based on the scale) that you'll probably need about 2 1/2 ounces of nose weight and you should have a dead straight flight. Another bonus, you'll actually have room for a decent sized parachute in this one.

Gotta keep with tradition.
What size and color chute do y'all want?

Evil Ed:evil:

 

[JAL3]

Gotta keep with tradition.
What size and color chute do y'all want?

Evil Ed:evil:

You mean you think he should use th 6" black one like I did in my clone? :surprised:

It works well there!

Blades: I like his chutes. They're nice.

 

[JAL3]

The built up launch lug I had put together earlier was glued to the BT with yellow glue. The paper wraps I had used to join the lugs acted like small standoffs were used to do the actual gluing. I set the lub back just far enough to protrude penetrate the aft bulkhead.

 

[JAL3]

The body tube was inserted into the after bulkhead, aligned and epoxied into place.

 

[JAL3]

When the epoxy joint between the bulkhead and the BT was firm, the assembly was slid into the shroud as far forward as it could go. The impression of the launch lug could be seen on the shroud and an X-acto was used to cut a notch to pass it. The tube and bulkhead were then seated the rest of the way forward and glued into place.

 

[JAL3]

As the bulkhead and BT assembly was drying into place in the shroud, I glued the cockpit into place with white glue. I decided to go with the more rounded version since it seemed to fit the contours of the rocket better.

 

[les]

Looking great - I really want one!!
Can't wait for a flight report!

 

[JAL3]

Looking great - I really want one!!
Can't wait for a flight report!

This satruday if all goes well!

 

[JAL3]

I had the shroud flued in place and the BT extended quite a bit in front. Now that everything was positioned as I wanted it, it was time to cut the excess BT from the front of the rocket. I used the shroud as a guide to draw an X-acto blade around the tube multiple times. Each time went a little deeper until the tube was cut.

 

[JAL3]

One of the things that worries me about this rocket is the stress on the appendages under the boost of a midpower motor. The fins, tail and scoop were all put on with white glue. To strengthen the joints, I mixed some epoxy and filleted the joints. I have no doubt this is stronger but it very much affected the appearance of the shrouds wherever the epoxy was in contact. To remedy this, I set the Vulcan up in the spray booth and began to give it multiple coats of Krylon Clear. This mimmicked the "wet" appearance of the epoxy and the the rocket a more uniform appearance.

 

[JAL3]

Evil Ed and Hartle Engineering come through again.

I came home from the church for lunch and there was a priority mail envelope sitting on my desk. I expected that it would be the chute he promised to send and I was only partly right. It also contained an additional assortment of chutes and streamers in other sizes and some launch lugs that look...different.

Let me be clear that this largess, pure and simple. He sent them out of the kindness of his Evil Ed heart. I thank him. My vulcan thanks him. All those people tomorrow who will not have to run to avoid ballistic recovery thank him.

BRAVO, HARTLE ENGINEERING.

 

[evil ed]

Evil Ed and Hartle Engineering come through again.

I came home from the church for lunch and there was a priority mail envelope sitting on my desk. I expected that it would be the chute he promised to send and I was only partly right. It also contained an additional assortment of chutes and streamers in other sizes and some launch lugs that look...different.

Let me be clear that this largess, pure and simple. He sent them out of the kindness of his Evil Ed heart. I thank him. My vulcan thanks him. All those people tomorrow who will not have to run to avoid ballistic recovery thank him.

BRAVO, HARTLE ENGINEERING.

"Kindness of his Evil Ed heart" my hinie! That stuff is gonna cost ya a pic, posted right here, of that Vulcan coming down under one o' my chutes!

The other stuff was used for packing so the chutes didn't get damaged in shipping.

The launch lugs are 1/4" mylar lugs that www.jonrocket.com peddles. When I need a large launch lug, these things are great!

Enjoy!

Evil Ed

 

[JAL3]

"Kindness of his Evil Ed heart" my hinie! That stuff is gonna cost ya a pic, posted right here, of that Vulcan coming down under one o' my chutes!

The other stuff was used for packing so the chutes didn't get damaged in shipping.

The launch lugs are 1/4" mylar lugs that www.jonrocket.com peddles. When I need a large launch lug, these things are great!

Enjoy!

Evil Ed

What I'm actually trying for is a pic on the pad before launch, a pic on the ground after recovery and a video for that more drawn out part in the middle.

I just got back from putting my gear together for in the morning. The chute is assembled and in place with barrel swivels. I went by Rebel Hobby earlier and got a few Roadrunner Fs and Gs. Tomorrow is looking up.

 

[JAL3]

The maiden flight of the Vulc 60 was on a Roadrunner F60-4. It took off and emulated the behavior of its smaller sibling, wagging its tail all the way. The chute deployed on time and it drifted down not too far away. I did learn that the baffle was not enough by itself to protect the chute in this rocket. There was a bit of shredding and lots of little holes. Even so, I judged it worthy of another flight.

The video of the first flight can be seen here: https://www.flickr.com/photos/23694991@N03/3013706193/

For the second flight, I wanted to try a Roadrunner G80. I learned, however, that this particular motor would not fit in the motor mount. An Aerotech G would because of the smaller diameter at the ejection end. I loaded an AT G77-7R. It took off and flew well but still corkscrewed. It was noticed, however, that the corkscrewing did not begin until well into the flight. Upon recovery, a small tear was noticed in the shroud. It did not seem to be from landing.

The video of the second flight can be seen here: https://www.flickr.com/photos/23694991@N03/3014606936/

 

[evil ed]

Sweet!

 

[Blades]

Very cool!! I see what you mean by the corkscrew though. I did not see any of that while flying my 55 version. Where does your 60 balance out?

 

[JAL3]

Very cool!! I see what you mean by the corkscrew though. I did not see any of that while flying my 55 version. Where does your 60 balance out?

I'll have to put a tape on it. Right now its sitting in the truck and I haven't unlaoaded it yet. Maybe after church this morning.

 

[JAL3]

I just realized that the link I provided for the first flight was wrong. The Vulcan was supposed to fly but the Little Joe took off instead. THe correct video link for the first flight is here: https://www.flickr.com/photos/23694991@N03/3014567860/in/set-72157608776787211/

Sorry

 

[Blades]

I did a little guesstimation, and based on where the 55 balances, your 60 should balance empty about 13 1/4" from the rear. Hope this helps.

 

[JAL3]

I did a little guesstimation, and based on where the 55 balances, your 60 should balance empty about 13 1/4" from the rear. Hope this helps.

I plan to check on it whenever I get a chance to get back to the shop. Right now, its like I'm being punished for having taken all of Saturday off. My boss even expected me to get up and come in to work early on Sunday!:surprised:

 

[JAL3]

On its maiden flight, the BT60 Vulcan came down with a slight rip in its shroud just forward of the cockpit. It did not seem to be a landing injury and my best hypothesis is that a swivel banged it when the chute deployed. It seemed safe to fly again and did fly again with no further injury.

 

[JAL3]

I opened the PDF file of the shroud in Photoshop and cropped out an area corresponding to the tear. I then printed it on regular bond paper.

 

[JAL3]

Using a pair of scissors, I further trimmed the patch to where it was just bigger than the tear. I then spread a small amount of white glue on the back and set it in place, trying to get the lines to line up. The patch was then smoothed down.

 

[JAL3]

I tried to celebrate my brithday by conducting a few unauthorized launches today. When I got there, I found I had forgotten all but the 1/4" rod and that limited my choices considerably. An easy choice was the Vulcan 60. I launched it on a RR F45-5. It went off fine and recovered fine but I found that the entire nosecone except for the part tied to the cord had snapped off. Back to the drawing board.

A vid can be seen here: https://www.flickr.com/photos/23694991@N03/3049049572/